New brain implant warns of epileptic seizures minutes before they happen

One of the worst things about epilepsy is its unpredictability. There is no way of knowing when those who struggle with the condition will have a seizure, nor any way to prepare for one. Or, at least, there wasn’t.

Researchers at the University of Melbourne are working on a brain implant that would be able to warn of seizures minutes in advance, giving their owners the chance to get ready as much as possible. By learning of an oncoming attack beforehand, they can remove themselves from any situation where a seizure would present a safety risk to themselves or others, such as operating heavy machinery or driving a car.

The project is headed up by Mark Cook, with funding from a U.S.-based medical device company called NeuroVista. At first, the implant’s software tracks the brainwave activity of its wearer, so that it can “learn” what kind of activity registers as unusual and potentially preparatory for a seizure. When it has enough data to make that prediction, the device will notify the user as soon as such activity is detected by transmitting a signal to a receiver worn outside their clothing.

In tests, 15 people with epilepsy tried the system for four months, and successfully predicted seizures for 11 of them 65 percent of the time. For two in particular, the device successfully warned of seizures every time one was about to occur, with a rough “warning time” of around four minutes before the seizure begins. “You can’t stop [the seizures],” Cook told New Scientist, “but if you knew one was going to happen, you could prepare… Just being able to predict them could improve people’s independence enormously.”

One unusual side effect of the trial was discovering that the device recorded seizures test subjects themselves weren’t even aware of. One subject in particular believed that he had only suffered 11 seizures during the test period, while information from the device suggested that the number was almost ten times that at 102. Christian Elger, who works at the University of Bonn in Germany, says this isn’t a new phenomenon. Studies suggest that patients tend to only realize of a quarter of their seizures.

Elger is hopeful about the implant’s use in future, noting that it could help with anti-seizure medication, which can take up to 15 minutes to have an effect and are often useless once a seizure has begun. With advance warning, it might be possible to administer medication ahead of time to prevent the seizure in the first place, he believes.

Tests continue to perfect the system; if nothing else, the fact that the system didn’t appear to offer significant predictive benefits for four of the test subjects at all is worth investigating. Still, sooner than later, there may be significant help on the way for their hopes to lead a less dangerous life.